Officers said the Capitol Federal Savings bank at 5700 Nieman Road was robbed about 3:40 p.m. by a man with a gun.

He left with a bag full of cash in a white plastic bag.

Investigators said the robber is black or Hispanic, about 5 feet 6 inches tall, 170 pounds with an average build. He was wearing a gray or black hooded sweatshirt, black jacket, a white face mask and jeans.

There's a $30,000 reward for information leading to the conviction of a bank robbery trio known as the Black Hat Bandits, suspected in a two-month string of robberies across Maryland and Virginia, the latest coming Monday.